Bird Technologies 4527 - Manual (Page 40)

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Peak Calibration
If recalibration is required, refer to figure 15 and these instructions:
1.
Unscrew the four 8-32 flat head screws securing the back cover.
2. Grasp the back cover by the side tabs behind the line connectors and pull
straight back to remove it.
3. Insert the Bird 43P between a reliable CW signal source and a 50 ohm load.
4. Insert an element with the appropriate power and frequency range into the
Bird 43P. Turn it to read forward power.
5. Set the wattmeter to CW mode (LED off).
6. Turn on the signal source and adjust the source power to give a stable read-
ing in the upper half of the wattmeter’s scale.
7. Switch the wattmeter to PEAK mode (LED on).
8. Adjust the potentiometer (R9) until the PEAK reading is the same as the CW
reading.
9. Replace the back cover.
Maintenance
Maintenance of the Bird 43P is the same as for the Bird 43 except for battery
replacement. Battery life should typically be 48 hours.
If the unit does not function properly in peak mode or if calibration cannot be
achieved, the batteries may be low. Replace with two new 9 V alkaline or lithium
batteries. The batteries fit very tightly in their retaining clips and may have to be
pried out one at a time.
Figure 13 Model 43P
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U1
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